Encapsulation of readily oxidizable components

Abstract

A stabilized emulsion is employed to produce shelf stable, controlled release, discrete, solid particles or pellets which contain an encapsulated and/or embedded component, such as a readily oxidizable component, such as omega-3 fatty acids. An oil encapsulant component which contains an active, sensitive encapsulant, dissolved and/or dispersed in an oil is admixed with an aqueous component and a film-forming component, such as a protein, to form an emulsion. The emulsion is admixed with a matrix material for obtaining a formable mixture or dough. An acidic antioxidant for prevention of oxidation of the active, sensitive encapsulant, and a plasticizer which solubilizes the acidic antioxidant are included in the matrix material which encapsulates film-coated oil droplets containing the readily oxidizable component. The plasticizer, such as glycerol, provides mobility for the acidic antioxidant within the matrix material of the pellets for reaction with any ambient oxygen and malodorous amines.

1. An encapsulated product comprising
 a) oil droplets comprising at least one polyunsaturated fatty acid, 
 b) a film-forming component comprising a protein, said film-forming component coating said oil droplets, 
 c) at least one matrix material encapsulating the film-coated oil droplets, 
 d) an acidic antioxidant dispersed throughout said matrix material, and 
 e) a liquid plasticizer which plasticizes said at least one matrix material and which provides mobility to said acidic antioxidant in the plasticized matrix material, 
 
       wherein said film forming component surrounds said oil droplets, and said matrix material and said acidic antioxidant surround the film-coated oil droplets, so that the acidic antioxidant can react with any ambient oxygen which enters the pellet interior or matrix material to prevent the oxygen from penetrating into the film-coated oil droplets. 
     
     
       2. An encapsulated product as claimed in  claim 1  wherein said oil droplets comprise fish oil or flax seed oil. 
     
     
       3. An encapsulated product as claimed in  claim 2  wherein said acidic antioxidant comprises at least one member selected from the group consisting of citric acid, ascorbic acid, erythorbic acid and salts thereof, and said liquid plasticizer comprises at least one polyol. 
     
     
       4. An encapsulated product as claimed in  claim 3  wherein said at least one polyol comprises at least one member selected from the group consisting of glycerol, propylene glycol, and sorbitol, and said film forming component comprises at least one caseinate. 
     
     
       5. A food product for animal or human consumption comprising an encapsulated product as claimed in  claim 1 . 
     
     
       6. A food product as claimed in  claim 5  which is selected from the group consisting of baked goods, ready-to-eat breakfast cereals, hot cereals, pasta products, fruit snacks, salty snacks, grain-based snacks, microwave popcorn, yoghurt, cheese, and ice cream, hard candy, soft candy, and chocolate, beverages, animal feed, pet foods, aqua-culture foods, baby food, infant formulas, hospital food, medical food, sports food, performance food or nutritional bars, or fortified foods, preblends for soups or gravy, dessert mixes, dinner mixes, cookie mixes, bread mixes, cake mixes, baking flour, and nutrient clusters. 
     
     
       7. An encapsulated product as claimed in  claim 1  wherein at least substantially all of the oil droplets have a diameter of less than about 2 microns, said film forming component surrounds said oil droplets, and said matrix material and said acidic antioxidant surround the film-coated oil droplets. 
     
     
       8. An encapsulated product as claimed in  claim 1  wherein the amount of said acidic antioxidant is up to about 18% by weight, based upon the weight of the encapsulated product. 
     
     
       9. An encapsulated product as claimed in  claim 1  wherein the acidic antioxidant comprises erythorbic acid and salts thereof. 
     
     
       10. An encapsulated product as claimed in  claim 1  wherein said matrix material comprises durum wheat flour or protein derived from wheat. 
     
     
       11. An encapsulated product as claimed in  claim 2  wherein the amount of the acidic antioxidant in the matrix material is from about 10% by weight to about 30% by weight, based upon the weight of the oil. 
     
     
       12. An encapsulated product as claimed in  claim 1  wherein said plasticizer comprises at least one member selected from the group consisting of glycerol, propylene glycol, and sorbitol, and the amount of said plasticizer is from about 10% by weight to about 20% by weight, based upon the weight of the encapsulated product. 
     
     
       13. An encapsulated product as claimed in  claim 1  wherein the microencapsulation efficiency is greater than about 85%. 
     
     
       14. An encapsulated product as claimed in  claim 1  wherein the amount of the matrix material is at least about 30% by weight, based on the weight of the encapsulated product. 
     
     
       15. An encapsulated product as claimed in  claim 1  wherein the amount of the acidic antioxidant employed in the matrix material is from about 1% by weight to about 40% by weight, based upon the weight of the oil. 
     
     
       16. An encapsulated product as claimed in  claim 15  wherein the amount of the acidic antioxidant employed in the matrix material is from about 15% by weight to about 25% by weight, based upon the weight of the oil. 
     
     
       17. An encapsulated product as claimed in  claim 1  wherein said acidic antioxidant is admixed with said liquid plasticizer to obtain a substantially homogeneous antioxidant solution, and said antioxidant solution is admixed with said matrix material to at least substantially plasticize said matrix material and to substantially uniformly distribute said antioxidant throughout said matrix material. 
     
     
       18. An encapsulated product as claimed in  claim 1  wherein the amount of the acidic antioxidant employed in the matrix material is from about 10% by weight to about 30% by weight, based upon the weight of the oil, and said film-forming component comprises a caseinate. 
     
     
       19. An encapsulated product as claimed in  claim 1  which is in the form of a pellet wherein the amount of acidic antioxidant employed in the matrix material is from about 0.5% by weight to about 4% by weight, based upon the weight of the pellet.